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Journal of Advanced Ceramics 2017年第2期6卷 149-156页

作者： bin deng Danyu JIANG Department of the Prosthodontics Chinese PLA General Hospital Beijing 100853 China Analysis and Testing Center for Inorganic Materials State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Shanghai 200050 China

Accurate estimation of Weibull parameters is an important issue for the characterization of the strength variability of brittle ceramics with Weibull *** this paper,a simple method was established for the determination of the Weibull parameters,Weibull modulus m and scale parameter σ0,based on Monte Carlo *** was shown that an unbiased estimation for Weibull modulus can be yielded directly from the coefficient of variation of the considered strength ***,using the yielded Weibull estimator and the mean value of the strength in the considered sample,the scale parameter σ0 can also be estimated accurately.

关键词： Weibull distribution Weibull parameters strength variability unbiased estimation coefficient of variation

Solutions for a Class of Singular Nonlinear Boundary Value Problem Involving Critical Exponent

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Acta Mathematicae Applicatae Sinica 2008年第3期24卷 453-472页

作者： Yin-bin deng Li Wang School of Mathematics and Statistics Central China Normal University Wuhan 430079 China

In this paper, we consider the existence of multiple solutions for a class of singular nonlinear boundary value problem involving critical exponent in Weighted Sobolev Spaces. The existence of two solutions is established by using the Ekeland Variational Principle. Meanwhile, the uniqueness of positive solution for the same problem is also obtained under different assumptions.

关键词： Variational methods singular boundary value problem multiple solutions

NONLINEAR EVOLUTION ANALYSIS OF T-S DISTURBANCE WAVE AT FINITE AMPLITUDE IN NONPARALLEL BOUNDARY LAYERS

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Applied Mathematics and Mechanics(English Edition) 2002年第6期23卷 660-669页

作者： TANG deng-bin(唐登斌) XIA Hao(夏浩) Department of Aerodynamics Nanjing University of Aeronautics and Astronautics Nanjing 210016 P R China Department of Aerodynamics Nanjing University of Aeronautics and Astronautics Nanjing 210016 P R China

The nonlinear evolution problem in nonparallel boundary layer stability was studied. The relative parabolized stability equations of nonlinear nonparallel boundary layer were derived. The developed numerical method, which is very effective, was used to study the nonlinear evolution. of T-S disturbance wave at finite amplitudes. Solving nonlinear equations of different modes by using predictor-corrector and iterative approach, which is uncoupled between modes, improving computational accuracy by using high order compact differential scheme, satisfying normalization condition I determining tables of nonlinear terms at different modes, and implementing stably the spatial marching, were included in this method. With different initial amplitudes, the nonlinear evolution of T-S wave was studied. The nonlinear nonparallel results of examples compare with data of direct numerical simulations (DNS) using full Navier-Stokes equations.

关键词： boundary layer stability nonlinear evolution nonparallelism T-S disturbance wave compact scheme spatial mode parabolized stability equation

Hybrid micromotion-scattering center model for synthetic aperture radar micromotion target imaging

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Journal of Systems Engineering and Electronics 2013年第6期24卷 931-937页

作者： Yuliang Qin bin deng Zonghui Huang Wuge Su School of Electronic Science and Engineering National University of Defense Technology

Micromotion is an important target feature, although the target micromotion has an unfavorable influence on the synthetic aperture radar （SAR） image interpretation due to defocusing. This paper introduces micromotion parameters into the scattering center model to obtain a hybrid micromotion-scattering center model, and then proposes an optimization algorithm based on the maximal likelihood estimation to solve the model for jointly obtaining target motion and scattering parameters. Initial value estimation methods using targets＇ ghost images are then presented to guarantee the global and fast convergence. Simulation results show the effectiveness of the proposed algorithm especially in high precision estimation and multiple targets processing.

关键词： synthetic aperture radar (SAR) micromotion microDoppler parameter estimation scattering center model

Angular extent effect of micromotion target in SAR image by polar format algorithm

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Journal of Systems Engineering and Electronics 2014年第3期25卷 428-433页

作者： bin deng Yuliang Qin Hongqiang Wang Yanpeng Li School of Electronic Science and Engineering National University of Defense Technology

Target micromotion not only plays an important role in target recognition but also leads to esoteric characteristics in synthetic aperture radar （SAR） imaging. This paper finds out an interesting phenomenon, i.e. the angular extent effect, in micro-motion target images formulated by the polar format algorithm. A micromotion target takes on multiple pairs of paired echoes （PEs） around the true point, and each PE extends for an angle which is exactly equal to the angular extent of the synthetic aperture, regardless of the micromotion frequency. The effect is derived and interpreted by using the characteristics of Bessel functions. Then it is demonstrated by simulation experiments of a target with different micromotion frequencies. The revelation and interpretation of the effect is highly beneficial to micromotion-target SAR image understanding as wel as target recognition.

关键词： synthetic aperture radar (SAR) micromotion micro-Doppler polar format algorithm (PFA) angular extent effect.

Radar cross section of arbitrary polished spheres at terahertz frequencies

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1072-1077页

作者： Ruijun Wang bin deng Hongqiang Wang Yuliang Qin College of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073China Uint 95876 of PLA Zhangye 734100China

We develop an efficient method for polished metallic sphere’s scattering prediction in terahertz band when its frequency dispersion property is considered. By deducing scattering solution of the lossy metallic sphere, the radar cross section(RCS)of different metallic spheres is given at terahertz frequencies. The investigation of the RCS of polished metallic spheres shows the normalized RCS is always same to the metals’ normal incidence reflectivity when the sphere becomes electrically large. The metals which have high reflectivity(such as Al, Cu, Ag and Au) show that the corresponding RCS of the spheres is almost πa2 in terahertz band. The sphere’s RCS of the transition metal such as Fe begins to decrease obviously since the far infrared.

关键词： terahertz radar cross section(RCS) sphere Drude model frequency dispersion

Fast motion estimation algorithm of video stabilization system

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Journal of Beijing Institute of Technology 2014年第1期23卷 102-107页

作者： WU Hao deng Hong-bin School of Information and Electronics Beijing Institute of Technology Beijing 100081 China School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China

A real-time electronic image stabilization motion estimation method based on fast sub- block gray projection algorithm is proposed. In the method, each image is divided into a number of sub-blocks, and sub-blocks are sifted with their gray gradients. After removing sub-blocks whose gray gradients are lower than the given threshold, the calculation amount of projection is reduced and the motion estimation accuracy is improved. Then gray projection is done in each remained sub- block, and global motion vector of the image is calculated according to the local motion vectors of sub-blocks and the affine motion model. The drawbacks as the local motions reducing the global mo- tion estimation accuracy and traditional gray projection algorithm could not deal with rotation are re- solved well by this algorithm. The experiment results show that the algorithm is more accurate and efficient than the gray projection algorithm.

关键词： video stabilization motion estimation gray projection algorithm gray gradient

Does the long-term application of calcium superphosphate lead to an increase of the soil rare earth element contents？

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Journal of Environmental Sciences 2006年第1期18卷 130-134页

作者： ZHANG Yun deng Li-bin YE Wan-Hui South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China School of Resources and Environmental Science Hubei University Wuhan 430062 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

In order to test whether the long-term application of calcium superphosphate leads to an increase of the soil rare earth element contents, superphosphate fertilized soils were sampled and compared with superphosphate-free soils. Spectrophlame inductively coupled argon plasma atomic emission spectrophotometer （ICP-AES） was applied to quantify the rare earth elements （REEs）. The total rare earth element contents in calcium superphosphate from Zhijin County, west part of Guizhou Province, China （produced by the sulphuric acid treatment of the apatites） are about 2.54 mg/g. Between 38 and 189 gREEs/hm^2 per year （available for plants, estimated by 2% citric acid） will be introduced into the soil solution when applying 320 kg superphosphate/hm^2 per year. The long-term application of the latter will increase the REE content by about 18% in the soil surface layer in these areas. A statistically significant increase of the content of the rare earths in some cultivated soils should not be neglected.

关键词： rare earth elements calcium superphosphate soil

The Neumann Problem for a Class of Fully Nonlinear Elliptic Partial Differential Equations

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Analysis in Theory and Applications 2023年第4期39卷 330-356页

作者： bin deng School of Mathematical Sciences University of Science and Technology of ChinaHefeiAnhui 230026China

In this paper,we establish global C2 estimates to the Neumann problem for a class of fully nonlinear elliptic *** an application,we prove the existence and uniqueness of k-admissible solutions to the Neumann problems.

关键词： Neumann problem fully nonlinear elliptic equation

Protective Effects of Berberine on Nonalcoholic Fatty Liver Disease in db/db Mice via AMPK/SIRT1 Pathway Activation

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Current Medical Science 2024年第5期44卷 902-911页

作者： Cheng CHEN Xiao-cui LIU bin deng Jingzhou Hospital Affiliated to Yangtze University Jingzhou434020China Department of Pharmacy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of Sciences Beijing100049China

Objective Berberine(BBR)has emerged as a promising therapeutic agent for nonalcoholic fatty liver disease(NAFLD).This study aims to elucidate the underlying molecular *** In this study,db/db mice were chosen as an animal model for NAFLD.A total of 10 healthy C57BL/6J mice and 30 db/db mice were randomly allocated to one of 4 groups:the normal control(NC)group,the diabetic control(DC)group,the Metformin(MET)therapy group,and the BBR therapy *** total cholesterol(TC),triacylglycerol(TG),low-density lipoprotein cholesterol(LDL-c),high-density lipoprotein cholesterol(HDL-c),aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels in the serum were *** glutathione peroxidase(GSH-Px),glutathione(GSH),malondialdehyde(MDA),superoxide dismutase(SOD),catalase(CAT),interleukin(IL)-1β,tumor necrosis factor(TNF)-αand monocyte chemotactic protein 1(MCP-1)levels in liver tissue were *** and eosin(H&E),acid-Schiff(PAS)and TUNEL stanning was performed for histopathological *** blotting and immunohistochemistry were conducted to detect the expression levels of key proteins in the AMPK/SIRT1 *** BBR could improve lipid metabolism,attenuate hepatic steatosis and alleviate liver injury *** excessive oxidative stress,high levels of inflammation and abnormal apoptosis in db/db mice were reversed after BBR *** clearly changed the expression of AMP-activated protein kinase(AMPK)/Sirtuin 1(SIRT1),and their downstream *** BBR could reverse NAFLD-related liver injury,likely by activating the AMPK/SIRT1 signaling pathway to inhibit oxidative stress,inflammation and apoptosis in hepatic tissue.

关键词： nonalcoholic fatty liver disease berberine inflammation oxidative stress apoptosis